Sectional tower



April 1, 1958 R. w. WEEKS 2,828,841

SECTIONAL TOWER Filed NOV. 4, 1949 FIGJL INVENTOR. Rosana w. WEEKS ATTORNEY WW a; MW

Unite States atent SECTIONAL TOWER Robert W. Weeks, West Chester, Pa., assignor to Wind Turbine Company, a corporation of Pennsylvania Application November 4, 1949, Serial No. 125,455

8 Claims. (Cl. 189-13) ice the length of the plate and has a depth less than the 'radius of a spar. As shown in Figure 1, the clamping plates are secured to the ends of the spars so that one-half the length of each plate extends beyond the end of the spar, and the plates at opposite ends of avspar are positioned on opposite sides of the spar. The free or un-attached side portion of each coupling plate extends laterally from its supporting spar into the triangular space within the tower, and each plate is provided with holes in the free side portion for receiving clamping bolts 4. Preferably each clamping plate is provided with a cam surface in the form of an ear 3a formed on one end thereof which is bent to form an inclined cam surface that will engage the end edge of the opposite coupling member on the adjacent vertical spar when two sections are placed in aligned abutting relation.

A primary object of the invention is to provide a lightweight, strong, easily erected tower or mast.

Another object is to provide a tower section which is easily and inexpensively manufactured.

Still another object is to provide a tower which is easily climable and presents very little resistance to high winds.

A further object is to provide a sectional tower with exceedingly simple and effective couplings for coupling two or more sections together to form a rigid unitary structure.

A preferred form of the invention is shown in the accompanying drawing in which:

Figure 1 is an elevational view of one section of the tower;

Figure 2 is an end view of the tower section shown in Figure l;

Figure 3 is a rear view on an enlarged scale of the joint between sections;

Figure 4 is a side view of the joint shown in Figure 3;

Figure 5 is a section view taken along the line 55 of Figure 4;

Figure 6 is a rear view of a modified joint; and

Figure 7 is a side view of the modified joint.

Figure 1 shows the preferred construction of a section of the tower which comprises three vertical spars 1a, 1b, 10 joined by serpentine bracing members 2a, 2b, 20, thus forming a triangular cross-section with the vertical spars at the apices of the triangle and the serpentine bracing members forming the sides of the triangle (see Figure 2). The loops of the serpentine bracing members 2a, 2b, 20 extend over and beyond the vertical spars 1a, 1b, 1c and are welded to the vertical spars at the two points at which they cross the spars as indicated by 2d and 2e in Figure 1. The end legs 2a, 2b, 2c of the serpentine bracing members at both ends of the section are bent so as to be perpendicular to the vertical spars as shown in Figure 1. The three end legs 2a, 2b and 2c are located in common transverse plane and provide a very rigid lateral bracing for the spars at each end of the section. After the section has been assembled, the ends of the vertical spars are accurately ground to exact length and at right angles to the axis of the section to assure proper alignment when several selections are clamped together. Coupling members 3 are then rigidly attached, preferably by welding, to both ends of each vertical spar. These coupling members are in the form of one-half part of a clamp, the complemental part of each clamp being carried on the end of the adjoining spar of the next section. Each clamp part is formed of a plate 3 having a channel formed along one side portion thereof for receiving the end of a spar. The spar receiving channel extends throughout Figures 3, 4 and 5 show the coupling construction in detail. Vertical spar la, with coupling member 3 attached thereto, abuts vertical spar 1a of an adjacent tower section. As shown in Figure 3, coupling plate 3 secured to spar 1a overlaps coupling plate 3 carried by spar 1a. The upper end portion of spar 1a is received in the lower half of the channel of plate 3' and the lower end portion of spar 1a is received in the upper half of the channel of plate 3. When the coupling members 3 and 3' are drawn together by a pair of bolts 4 passing through the two overlapping plates, the ears 3a and 3a engage the end edges of the opposite coupling members and, by cam action between the end edge of one coupling member engaging the inclined surface of the car on the opposite coupling member, the two vertical spars 1a and 1a are drawn together, thereby firmly joining adjacent tower sections. This coupling design places the clamping bolts 4 under tensile stress but does not subject them to a shearing stress, it being understood that the holes in the plates receiving bolts 4 provide sufficient clearance around the bolts to permit limited axial movement of the two plates with respect to each other as the plates are beingdrawn together.

- Figures 6 and 7 show a modified form of coupling in which the inclined cam surface is formed by inclined shoulders 3b and 3b formed on the inner faces of coupling members of plates 3 and 3' substantially at the midpoint of the members. In this case coupling plates 3 and 3 are secured to spars 1a and 1a, respectively, the same as in Figure 3, and the cam action for drawing the ends of the two spars together is produced by engagement of the two inclined shoulders 3b and 3b, as shown in Figure 6.

1 From the foregoing description, and from the drawing, it will be noted that the holes for the clamping screws 4 are formed in the longitudinal side portions of the coupling plates which extend laterally from the spars and into the polygon area (the transverse area of the tower) bounded by the outer surfaces of the bracing members and the spars. Also, it will be noted that the coupling plates secured to opposite ends of each spar are arranged on opposite sides of a common plane passing through the long axis of the common mounting spar.

In both forms of coupling the two coupling members are of identical construction. It will also be noted that the clamping plates are secured to the spars so that the parts which are bolted together extend inwardly of the mast, thereby protecting the coupling members from injury and avoiding projecting parts which might cause trouble during assembly operations. It will be noted that in both forms of coupling the inclined cam surface on each coupling member is arranged to face back towards the spar upon which it is rigidly mounted, whereby uponengagement with the complemental coupling member carried by an adjacent spar, and upon pressing the two members together transversely of the spars, the two spars are drawn I towards each other into direct abutting contact.

While I prefer to construct the tower section of only three spars arranged in the form of a triangle. it will be obvious that more than three spars may be used'withdifferent spacing arrangements.

I claim:

1. A tower section comprising a plurality of spars arranged in parallel relation, bracing members joining said spars and holding them in transversely spaced relation to form an elongated hollow frame, a first set of coupling members secured to the end portions of said spars at one end of said section, each coupling member comprising an elongated plate element arranged-with its long axis parallel with the axis of thespar upon which it is mounted and being-secured to its spar along a portion of one longitudinal side portion thereof, eachplate element having a longitudinal end portionextending beyond the end of its mounting'spar, and each mounting pl-atehaving a free longitudinal side portion extending laterally from its mounting spar and into the inner space of said hollow frame, a second set of coupling elements secured to the ends of said spars "at the other end of said section. each coupling member of said second set comprising an elongated plate element arranged with its long axis parallel with the axis of the sparupon which itis mounted and being secured to its mounting spar along'a portion of onelongitudi nal side portion thereof, and each of said second set of mounting plateshaving a longitudinalend portion extending beyondthe' end of its mounting spar and having a free longitudinalside portion'extending laterally from its mounting spar-andinto theinner space .of said hollow frame, the free longitudinal side portions of said coupling plates having holes formed therein for receiving clamping bolts, and the free longitudinal side portions of the coupling plates at'opposite ends of each spar being located on opposite sides of a commonplane passing through the long axis of the common mounting spar.

-2. 'Atower section-according to claim 1 wherein each longitudinalzend'extensi'on on said coupling members is provided with a channel in one face thereof for receiving the end of a spar in an adjacent tower section and holding said end in aligned and abutting relation with the end of the spar to which said coupling member is secured.

3. A tower section according to claim 1, wherein the ends of said spars at each end of said section are accu- 'rately Lground .so-that theend surfaces are located in a common plane at rightangles to the'axis of said section.

4. A-coupling for a pair-of aligned spars or rods corn.- prising in combination withnsaid spars, a pair of overlapping-clamping plateszarranged in parallel relation onopposite sides of the abutting ends of said spars, means securing one clampingplate to thelend. portion of one spar, means securing the other clamping plate to the end portion of the second spar, said clamping plates overlapping said spars transversely of the spars and each clamping plate having a channel formed in one face thereof receiving the end of-the oppositespar and holding said end in alignment with the spar to which the clamping plate is secured, clamping means for clamping .said plates together transversely of said spars, anda cam element .car-

ried by each plate and having an inclined cam surface engaging a portion of the opposite plate for drawing the ends of said spars together'when saidplates are drawn .together by said clamping means.

5. A coupling according to claim 4 wherein said cam element comprises an inclined ear formed on each clamping plate and having an inclined surface facing back towards its supporting spar and positioned to engage the end edge of the opposite clamping plate.

6. A coupling according to claim 4 wherein said cam element comprises an inclined shoulder formed on the face of each clamping plate, each'inclined shoulder facing back towards its supporting spar and being positioned to engage the inclined shoulder of the clamping plate on the opposite side of said coupling.

7. A coupling for a pair of aligned spars-with abutting ends-comprising, incombination with said spars, a pair of elongated coupling members arranged to overlap the joint between the abutting ends of-said spars and extending parallel with the axis of said spars, means securing one end portion of one coupling member to one spar, means securing one end portion of the other coupling member to the other spar, clamping means engaging overlapping portions'o f-said coupling member-s clamping-said members together transversely of said spars, and a cam elementcarried by at least one of said coupling members and having an inclined cam surface facing back towards the spar which supports said cam element and positioned in engagement with a portion of the other overlapping coupling member whereby when said overlapping coupling members are forced towards'each-other transversely of said spars, the adjacent ends of said spars are forced towards each other by theaction of said cam surface.

8. A coupling for apair of aligned spars with abutting ends comprising,'in combination with said spars, a pair ofelongated-coup'ling members arranged to overlap the joint between the abutting ends of said spars and extending parallel with the axis of said spars, means securing one end portion of one coupling'member to one spar, means securing one end portion ofthe "other couplingmember to the other spar, said clamping plates overlapping said spars transversely of the spars, clamping means engaging overlapping portions of saidcoupling members for clamping said members together transversely of said spars, and camming means comprisi-nga projection carried by one coupling member and extending into overlapping relation and in contact with a portion of the other coupling mem her and locking thetwocoupling members against relative axial movement by any force tending to separate the aligned-spars.

References Cited in the file of this patent UNITED STATES 1 PATENTS 147,837 .Heginbothom. Feb. 24,, 1874 774,371 .Altmyer'e Nov. 8, 1904 "946,093 Altmyer Ian. 11,.191-0 948,088 Craven Feb. 1, 1910 1,054,737 Woodbury Mar..4,.1913 1,332,669 Lachman Mar. 2, 1920 1,464,750 Davis- Aug. 14, 1923 1,486,549 Schuette Mar. 11, 1924 1,941,952 Nickles Jan. 2, 1934 2,194,810 Reiner Mar. 26, 1940 2,271,472 .:Balduf Jan.. 27, 1942 ..2,404,276 .Cohen .Iu1y 16, 1946 2,449,056 Clark Sept. 14, 1948 FOREIGN PATENTS 7,491 Great Britain of 1905 365,077 GreatBr'itain- Jan. 14, 1932 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 2,828, 841

April 1, 1958 Robert W. Weeks tion and that the said Letters read as corrected below.

Column 4, line 3'7 for "clamping plates" read coupling members 0 Signed and sealed this 26th day of August 1958,

(SEAL) Attest: KARL H. AXLINE ROBERT c. WATSON Attesting Officer Commissioner of Patents 

